Cast is heavier then machined normally

i just rebuilt a vspec for a local , he provided parts which i am pretty sure were arrow parts and all fit perfect , ran great

parts quality/finish nowhere near that of the japanese made vspec parts but crank seemed to be much harder steel (bonus) , needless to say the engine ran great

the piston looked "speckled" as you said marcus , maybe neal knows for sure but i am pretty sure the partsare a direct fit to the original OS engines bore x stroke combo

btw , the rod didnt look near as finished and in past experiences rods with sharp edged machining did not last

hope this helps

if your curious novarossi machined piston is quite a bit heavier than cast

I have a new speed rod, would that be better?

Did they make up tech lord just for you

Xray's Patrick Castleberry is now using the Arrow GTR-21 engine.

From needing some extra heat on the Arrow GTR .21 motor to first crank it over, I thought of making these.
Custom Machined from Steel 2.5 inch OD and bored to size for ID with about .015 clearance, also is milled out for exhuast port and around carb body, to concentrate heat to where its needed down thru the piston casing
http://www.youtube.com/watch?v=HnM_eHtNCxs
I have a few already to size for the Arrow GTR .21
$21.50 includes shipping, http://pages.suddenlink.net/hotheadsrc/

i have a few pipes to chose from atm: Losi RE10/RE11, JP2, JP4, Hong nor EFRA 2047.
So wich one would be best, i know 2060 and 9901 are best but dont realy want to sped 160$ for pipe atm.

Thanks

RE10 or jp4 would be good

TLR Driver, Ryan Lopez, TQ's and Wins 1/8 pro buggy at the Alabama Shootout 4.0 with the Arrow-Racing GTR-21 engine.

after doing some testing with this engine i highly recommend using a jp3 pipe on this engine

Did you test run times?

ya the jp3 pick up a min over the os 2060 and powerband is spot on with the jp3 engine didnt feel good on the 2060 and the 2035 the engine is all bottom and no top and gets about the same runtime as the 2060.

Wow that's impressive. That's the first time I've heard of any Jammin pipes with better runtimes than anything! Great feedback. Appreciate the test results.

Im about to pick up a nib "used" gtr, how can I tell if it has the updated v2 crank case, and of its v1 is that a big deal performance wise? When did this change over happen? THANKS!

The case was changed a few months back due to the front bearing coming out really easy. If you take the engine apart, and you pull the crank out and stick a wrench in the case and hit the front bearing it will fall out.

The bad thing with this is air leaks and fuel leaks from the front bearing. Also it does not seem to have the power of a sealed engine. You can replace the bearing, or get the new case from Hobby Pro and put all the parts you have one the new case.